Effect of Lymphocyte Phenotypic Alterations on the Humoral Response to Vaccination Against SARS-COV-2 in Dialysis Patients.

Background: The response to vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) varies depending on comorbidities. This study evaluated the clinical and immunological factors affecting the humoral response of patients with end-stage renal disease (ESRD) to the BNT162b2 vaccine. Methods: Humoral immunity was evaluated in 54 ESRD patients using serum levels of anti-receptor-binding domain (RBD) and neutralizing antibodies (NAbs), measured by a chemiluminescent immunoassay 30 (T1), 60 (T2), and 120 (T3) days after the second vaccine dose. The results were correlated to baseline patient T- and B-lymphocyte subpopulations determined by flow cytometry. Results: The proportion of seroconverted patients based on the NAb titer decreased from 83.3% at T1 to 53.7% at T3. Age was negatively correlated to the NAb titer at T1 and T2. Patients receiving hemodiafiltration had higher NAb titers at T3. Diabetes was associated with a lower response rate at T3. Univariate analysis revealed a positive correlation between the naïve CD4 T-lymphocyte population and RBD titer at T1 and the NAb titer at T3, with no association observed with naïve CD8 T lymphocytes. NAb titers at T3 were significantly correlated with late-differentiated CD4 T lymphocytes and terminally differentiated effector memory cells re-expressing CD45RA (TEMRA) CD8 T lymphocytes. RBD levels were positively correlated with naïve and memory B-lymphocyte counts at T3. Conclusions: Age, diabetes, and hemodialysis prescription had significant impacts on the response to vaccination. T- and B-lymphocyte phenotypes are major determinants of the humoral response potency to SARS-CoV-2 vaccination with BNT162b2 in patients with ESRD.

Hemodialysis Effects on Autonomic Function: Results of Linear and Nonlinear Analysis of Heart Rate Variability at Rest and in Response to Physical and Mental Stress Tests.

INTRODUCTION: Cardiac arrhythmias are the most common cause of death in hemodialysis. Autonomic dysfunction plays a central role in this arrhythmogenic background. Previous studies on hemodialysis-related changes in heart rate variability (HRV) give contradictory results. This study investigated HRV indices both at rest and in response to physical and mental stimulation maneuvers at multiple time-points around and during the hemodialysis procedure. METHODS: Autonomic function was assessed by linear and nonlinear HRV indices at predialysis, during dialysis (3 equal time-periods), postdialysis, and on the nondialysis day in 36 hemodialysis patients. Continuous measurement of beat-by-beat heart rate was recorded with Finometer-PRO (The Netherlands) at rest and after orthostatic, sit-to-stand, handgrip, and mental-arithmetic test. RESULTS: The RMSSD, SD1, and SD2 indices significantly increased during dialysis (early-HD, mid-HD, late-HD periods) compared with the predialysis levels (p < 0.05) and returned to baseline postdialysis (RMSSD: 54.39 ± 83.73 vs. 137.98 ± 109.53* vs. 119.85 ± 97.34* vs. 144.47 ± 88.74* vs. 85.82 ± 121.43msec, *p < 0.05 vs. predialysis and postdialysis). No differences were detected in the above indices between the predialysis and nondialysis day. However, postdialysis, the HRV responses to orthostatic and sit-to-stand tests were more exaggerated than in the predialysis measurements (p < 0.05). The HRV responses both at resting and physical tests in the nondialysis day were similar to the predialysis levels. HRV indices in the mental arithmetic test during hemodialysis were much higher than at the nondialysis day (RMSSD: 77.05 [180.41] versus 19.75 [105.47] msec; p = 0.031). CONCLUSIONS: Hemodialysis causes marked changes in the autonomic function. Resting HRV indices return to baseline postdialysis, but HRV responses to physical stress remain exaggerated and return to baseline on the nondialysis day. Detecting patients with significant autonomic dysfunction may help towards reduction of arrhythmia risk through individualized approaches.

Two Cases of Autoimmune Thyroid Disorders after COVID Vaccination in Dialysis Patients.

SARS-CoV-2 infection and vaccination have been associated with autoimmune thyroid dysfunctions. Autoimmune/inflammatory syndrome induced by adjuvants (ASIA) and molecular mimicry have been referred to as potential causes. Such a case has not been reported in immunocompromised end-stage renal disease (ESRD) patients. Herein we present two dialysis patients with no previous history of thyroid disease who developed immune mediated thyroid disorders after BNT162b mRNA vaccine against SARS-CoV-2. The first patient is a 29-year-old man on hemodialysis diagnosed with Grave's disease four months post-vaccination and the second one is a 67-year-old female on peritoneal dialysis who developed Hashimoto's thyroiditis two months post-vaccination. Grave's disease is uncommon in dialysis patients, whereas Hashimoto's thyroiditis has a higher incidence in this population. Time proximity in both cases suggests potential causality. To our knowledge, this is the first report of de novo immune-mediated thyroid disorders in dialysis patients following vaccination against SARS-CoV-2.

Clustering of End Stage Renal Disease Patients by Dimensionality Reduction Algorithms According to Lymphocyte Senescence Markers.

End stage renal disease (ESRD) engenders detrimental effects in the Immune system, manifested as quantitative alterations of lymphocyte subpopulations, akin, albeit not identical to those observed during the ageing process. We performed dimensionality reduction of an extended lymphocyte phenotype panel of senescent and exhaustion related markers in ESRD patients and controls with Principal Component Analysis (PCA) and Uniform Manifold Approximation and Projection (UMAP). The plane defined by the first two principal components of PCA showed two fuzzy clusters, for patients and controls, respectively, with loadings of non-senescent markers pointing towards the controls' centroid. Naive lymphocytes were reduced in ESRD patients compared to controls (CD4+CD45RA+CCR7+ 200(150-328) vs. 426(260-585cells/µl respectively, P = 0.001, CD19+IgD+CD27- 54(26-85) vs. 130(83-262)cells/µl respectively, P < 0.001). PCA projections of the multidimensional ESRD immune phenotype suggested a more senescent phenotype in hemodialysis compared to hemodiafiltration treated patients. Lastly, clustering based on UMAP revealed three distinct patient groups, exhibiting gradual changes for naive, senescent, and exhausted lymphocyte markers. Machine learning algorithms can distinguish ESRD patients from controls, based on their immune-phenotypes and also, unveil distinct immunological groups within patients' cohort, determined possibly by dialysis prescription.

Associations of serum sclerostin and Dickkopf-related protein-1 proteins with future cardiovascular events and mortality in haemodialysis patients: a prospective cohort study.

BACKGROUND: Sclerostin and Dickkopf-related protein-1 (Dkk-1) proteins are inhibitors of the canonical Wnt/ß-catenin bone pathway. Sclerostin but not Dkk-1 is associated with increased arterial stiffness. This study examined the prognostic significance of sclerostin and Dkk-1 levels for cardiovascular outcomes and mortality in haemodialysis (HD) patients. METHODS: Serum sclerostin and Dkk-1 levels were measured with enzyme-linked immunosorbent assay in 80 HD patients that were followed-up for a median of 45 months. Factors that could interfere with the association of sclerostin and Dkk-1 with outcomes [including carotid-femoral pulse wave velocity (PWV), parathyroid hormone (PTH), calcium-phosphate product and others] were assessed at baseline. The primary endpoint was a combination of all-cause death, non-fatal myocardial infarction, non-fatal stroke, coronary revascularization, hospitalization for decompensated heart failure and new-onset atrial fibrillation. Secondary endpoints included cardiovascular and all-cause mortality. RESULTS: Cumulative freedom from the primary endpoint was significantly lower for higher tertiles of sclerostin (77.8, 69.2 and 40.7%; Tertiles 1-3, respectively; log-rank P = 0.004). The risk for the primary outcome gradually increased for higher sclerostin tertiles [Tertile 3: hazard ratio (HR) = 3.847, 95% confidence interval (CI) 1.502-9.851]. No significant association was evident between sclerostin and all-cause mortality, whereas higher sclerostin levels presented a trend towards higher risk for cardiovascular mortality. Dkk-1 levels exhibited no association with the risk of the primary or secondary endpoints. In stepwise Cox regression modelled analysis, sclerostin levels were associated with the primary outcome, independently of PTH, calcium-phosphate product, serum albumin, C-reactive protein and PWV levels (HR = 2.921, 95% CI 1.401-6.090; P = 0.004). CONCLUSIONS: High sclerostin levels are associated with lower cumulative freedom and higher risk for a composite endpoint of cardiovascular events and mortality. Dkk-1 exhibited no association with the future risk of adverse outcomes.

TNF-α pathway and T-cell immunity are activated early during the development of diabetic nephropathy in Type II Diabetes Mellitus.

Aim of the present study was to investigate the possible involvement of TNF-α signaling pathway and T-lymphocyte activation in DN. Eighty-two diabetic patients [39 male, age 69.5(56-78)years] were divided into three groups, according to Albumin/Creatinine ratio (ACR) levels, Group I (ACR < 30 µg/mg), Group II (ACR 30-300 µg/mg), Group III (ACR > 300 µg/mg). Urinary Tumor Necrosis Factor-α (TNF-α), and serum TNF-α, ΤNF-receptor 1 (TNFR1), TNFR2, B7-1, CD28, Cytoxic T-Lymphocyte-Associated protein-4 (CTLA4), were estimated. There were significant differences between Groups I, II, III regarding the concentration of urinary TNF-α (p < .001), serum TNFR1 (p < .001), serum TNFR2(p < .001), CTLA4 (p < .001) and CD28(p = .034). In multivariate analysis, independent parameters correlated with ACR were serum TNFR1 (p = .003), TNFR2 (p = .012) and urinary TNF-α (p = .015) levels. There was a significant correlation between markers of T-cell activation and TNF-α signaling pathway activation. Activation of TNF-α signaling pathway and T-lymphocytes seem to synergize and participate in the development of DN in type II DM.

Increased Sclerostin, but Not Dickkopf-1 Protein, Is Associated with Elevated Pulse Wave Velocity in Hemodialysis Subjects.

BACKGROUND: Sclerostin and Dickkopf-1 (Dkk-1) proteins are inhibitors of the canonical Wnt/ß-catenin bone pathway. Pilot data suggest that sclerostin may be involved in vascular changes in chronic kidney disease (CKD), but data on the effects of Dkk-1 are scarce. This is the first study investigating simultaneously the associations of sclerostin and Dkk-1 with arterial stiffness in hemodialysis patients. METHODS: A total of 80 patients on chronic hemodialysis had carotid-femoral pulse wave velocity (PWV), central blood pressure (BP), and wave reflections evaluated with applanation tonometry (Sphygmocor) on a midweek non-dialysis day. Serum levels of sclerostin and Dkk-1 were measured with ELISA. A large set of demographic, comorbid, laboratory, and drug parameters were used in the analyses. RESULTS: Subjects with PWV >9.5 m/s (high arterial stiffness group, n = 40) were older, had higher BMI, higher prevalence of hypertension, diabetes, and coronary heart disease, and higher peripheral systolic BP, central systolic BP, C-reactive protein, and serum sclerostin (p = 0.02), but similar Dkk-1, compared to subjects with low PWV. When dichotomizing the population by sclerostin levels, those with high sclerostin had higher PWV than patients with low sclerostin levels (10.63 ± 2.71 vs. 9.77 ± 3.13, p = 0.048). Increased sclerostin (>200 pg/mL) was significantly associated with increased PWV (>9.5 m/s; HR 2.778, 95% CI 1.123-6.868 per pg/mL increase); this association remained significant after stepwise adjustment for Dkk-1, intact parathyroid hormone, and calcium × phosphate product. In contrast, no association was noted between Dkk-1 and PWV (HR 1.000, 95% CI 0.416-2.403). CONCLUSION: Serum sclerostin is associated with PWV independently of routine markers of CKD-MBD in hemodialysis patients. In contrast, Dkk-1 has no association with arterial stiffness and is not pathophysiologically involved in relevant vascular changes.

Soluble Klotho is associated with mortality and cardiovascular events in hemodialysis.

BACKGROUND: Klotho is a transmembrane protein acting as a co-receptor for FGF-23 and thus exerts clinical actions on mineral metabolism. The association of secreted Klotho with outcomes in CKD patients is unclear. This study examined the relation between plasma Klotho and cardiovascular events in dialysis patients, accounting for common and CKD-MBD related risk factors, arterial stiffness and atherosclerotic burden. METHODS: Seventy-nine chronic hemodialysis patients were observed for a median follow-up of 5.5 years. Klotho levels as well as carotid-femoral pulse wave velocity (cfPWV) and common carotid intima-media thickness (ccIMT) measurements were performed at baseline. The primary end-point was first occurrence of all-cause death, non-fatal myocardial infarction or non-fatal stroke. Secondary end-points were: (i) all-cause mortality; (ii) cardiovascular mortality; (iii) a combination of cardiovascular death, non-fatal MI, non-fatal stroke, resuscitation after cardiac arrest, coronary revascularization, heart failure hospitalization and atrial fibrillation. RESULTS: Cumulative freedom from the primary endpoint was 31% for the low-Klotho group (≤745 pg/ml) and 53% for the high-Klotho group (logrank p = 0.017); HR: 2.137, 95%CI 1.124-4.065. Cumulative survival was insignificantly lower (44% vs 56%, p = 0.107), but cumulative cardiovascular survival (63% vs 88%, p = 0.029) and cumulative freedom from the cardiovascular composite outcome (18% vs 45%, p = 0.009) were significantly lower in the low-Klotho group. In modelled Cox-regression analysis the association of low Klotho with the primary endpoint remained significant after stepwise adjustment for cFGF3, PTH, Ca x P product, established risk factors (age, dialysis vintage, diabetes, hypertension, smoking, history of cardiovascular disease) as well as cfPWV and ccIMT [Model 6: HR:2.759, 95%CI 1.223-6.224, p = 0.014]. CONCLUSIONS: Low Klotho is associated with cardiovascular events in hemodialysis patients, independently from factors associated with mineral-bone disease, common risk factors and intermediate outcomes, such as cfPWV and ccIMT.

Treatment of adynamic bone disease in a haemodialysis patient with teriparatide.

Prevalence of adynamic bone disease (ABD), characterized by low bone turnover and absence or a reduced number of osteoblasts and osteoclasts, is increasing steadily over the last years. We present a dialysis patient, with recurrent bone fractures and biopsy-proven ABD, who was treated with teriparatide. Nine months after initiation of treatment, iPTH plasma levels increased to 520 pg/mL and a second bone biopsy revealed high bone turnover, normal mineralization and normal bone volume. Two years later, iPTH was 250-350 pg/dL and bone metabolism parameters within normal range. The probable utility of teriparatide in the treatment of ABD in dialysis patients is discussed.

Detection of multiple cytokines in the urine of patients with focal necrotising glomerulonephritis may predict short and long term outcome of renal function.

BACKGROUND: Detection of urinary cytokines in pauci-immune focal segmental necrotizing glomerulonephritis (FSNGN) may provide valuable information about disease pathogenesis and prognosis. METHODS: Epidermal growth factor (EGF), transforming growth factor (TGF-ß1) and vascular endothelial growth factor (VEGF) were measured by ELISA, and Interleukins, monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein (MIP1ß) by a multiplex cytokine assay, in 38 patients with FSNGN. Their levels were correlated with severity of histological findings and renal function outcome in short and long term. RESULTS: The percentage of crescents in renal biopsy had positive correlation with TGF-ß1 (p=0.004) and IL-15 urinary excretion (p=0.01), and negative correlation with EGF (p=0.01). Increased urinary excretion of IL-6, IL-15, VEGF and MIP-1ß was associated with poor renal function outcome, but increased levels of EGF, IL-2 and IL-9 predicted a favourable prognosis. In multiple regression analysis IL-6 and VEGF urinary levels were independent predictors of no-response at the acute phase (p=0.001 and p<0.0001, respectively), while, IL-6 was the only factor (p=0.03) predicted worse outcome at the end of follow-up (39.4±45 months). CONCLUSION: Increased urinary excretion of IL-6, IL-15, VEGF, TGF-ß1, MCP-1 and MIP-1ß and reduced EGF, IL-2, IL-9 may be associated with histological damage and influence response to treatment in pauci-immune FSNGN.

Steroids and azathioprine in the treatment of IgA nephropathy.

AIM: IgA nephropathy (IgAN) is a very common glomerulonephritis among young adults, but the best therapeutic approach has not been fully elucidated. This study evaluated the effect of two different treatment regimes in IgAN, steroids alone or in combination with azathioprine. METHODS: Among 122 patients with primary IgA nephropathy diagnosed in the 2000-2007 period, 22 fulfilled the inclusion criteria for the study: estimated glomerular filtration rate (eGRF) ≥30 ml/min/1.73 m(2), urine protein (Upr) ≥1 g/24 h, blood pressure (BP) <130/80 mmHg, and previous treatment with renin-angiotensin system inhibitors (RAASi) and polyunsaturated fatty acids (PFA) for at least 6 months. Patients were randomized to receive either methylprednisolone alone (MP group) or MP in combination with azathioprine (MP + Aza group) for 12 months, while treatment with RAASi + PFA continued unchanged in both groups. RESULTS: At the completion of the trial, renal function in the MP group remained stable, eGFR from 52 ± 26.7 to 53.6 ± 27.3 ml/min/1.73 m(2), p = NS, and Upr decreased from 2.4 ± 0.9 to 0.8 ± 0.5 g/24 h, p < 0.001. In the MP + Aza group, eGFR slightly increased from 57.4 ± 28.7 to 66 ± 31 ml/min/1.73 m(2), p = NS, and Upr decreased from 2.4 ± 1 to 0.7 ± 0.7 g/24 h, p < 0.001. Four patients from the MP group with partial remission at the end of the trial had a complete response when converted to Aza. Eleven patients (5 from the MP and 6 from the MP + Aza group) relapsed after stopping treatment and were restarted on lower doses. CONCLUSIONS: Both, steroid treatment alone and steroids in combination with azathioprine seem to be effective in reducing the severity of proteinuria and stabilizing renal function in IgAN. Patients who do not respond to steroids may have a better response with the combination of steroids and azathioprine.

Acute kidney injury due to osmotic nephrosis following intraoperative placement of an intraperitoneal antiadhesive barrier.

In recent years, a common strategy for the prevention of postsurgical intra-abdominal adhesions has been intrasurgical placement of adhesion barriers into the peritoneal cavity. Osmotic agents, such as various polysaccharides, frequently are used as antiadhesive materials. The effects of these materials on kidney function have not yet been studied. We report a case of an individual with pre-existing chronic kidney disease who developed acute kidney injury after surgical placement of an antiadhesive barrier of macromolecular polysaccharides. A kidney biopsy, performed because of persistent kidney failure, showed tubular cell lesions compatible with osmotic nephrosis lesions. This case suggests that use of polysaccharide-containing antiadhesive barriers can induce severe kidney damage. Such barriers should be used with caution in patients with abnormal kidney function to prevent irreversible damage.

Polyarteritis nodosa in a patient with type 1 autoimmune hepatitis.

Polyarteritis nodosa is a systemic necrotizing vasculitis that affects small- and medium-sized arteries. Liver involvement in patients with polyarteritis nodosa has been described, and ranges from asymptomatic elevation of aminotransferases to hepatic aneurysm rupture. We describe the case of a patient with type 1 autoimmune hepatitis and compensated liver cirrhosis who developed classic polyarteritis nodosa, complicated with cytomegalovirus and repeated urinary tract infections. After a long bedridden hospitalization, the patient's condition was stabilized. She is currently in good health, with well-controlled blood pressure, and stable kidney and liver function. To our knowledge, this is the first case report in the literature with concurrent appearance of both diseases.

Circulating levels of ICAM-1, VCAM-1, and MCP-1 are increased in haemodialysis patients: association with inflammation, dyslipidaemia, and vascular events.

BACKGROUND: Increased levels of circulating adhesion molecules and chemokines have been reported in haemodialysis (HD) patients but the influence of the HD membranes on their secretion, as well as their pathophysiological implications, remains largely unknown. METHODS: Circulating levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and monocyte chemoattractant protein-1 (MCP-1) were measured by immunosorbent assay (ELISA) in 81 HD patients (45 male, mean age 57+/-13 years) and 35 normal subjects. All patients had been stabilized on renal replacement therapy for >3 months and were free of active infection. Thirty-three patients (40.7%) were routinely dialysed with modified cellulose membranes and 48 patients (59.3%) were dialysed with polysulfone membranes. Blood samples were taken directly from the arteriovenous fistula immediately before and at the end of a routine HD session. RESULTS: Pre-dialysis levels were significantly elevated in HD patients compared with controls (ICAM-1 515+/-177 vs 238+/-664 ng/ml, P<0.0001; VCAM-1 2107+/-648 vs 1012+/-115 ng/ml, P<0.0001; MCP-1 427+/-148 vs 125+/-42 pg/ml, P<0.0001). The HD session resulted in a significant increase in the levels of all three molecules measured (515+/-177 vs 679+/-187 ng/ml, P<0.0001; 2107+/-648 vs 2662+/-800 ng/ml, P<0.0001; 427+/-148 vs 567+/-153 pg/ml, P<0.0001, respectively). There was no difference in pre- or post-dialysis levels of the above molecules between patients routinely dialysed with either modified cellulose or polysulfone membranes. MCP-1 levels had a positive correlation with ICAM-1 levels (r=0.41, P<0.0005). VCAM-1 levels had a negative correlation with HDL levels (r=-0.30, P<0.01) and were significantly elevated in patients with HDL <35 mg/dl compared with patients with HDL > or = 35 mg/dl (2300+/-606 vs 1890+/-633 ng/ml, P<0.005). Log-transformed exact C-reactive protein (CRP) values were significantly correlated with ICAM-1 and VCAM-1 levels (r=0.41, P<0.005 and r=0.43, P<0.005, respectively). In addition, compared with patients with normal CRP values, patients with elevated CRP had significantly increased levels of ICAM-1 (466+/-166 vs 580+/-172 ng/ml, P<0.005). Patients with cardiovascular, cerebrovascular, or peripheral vascular diseases had significantly increased serum CRP and ICAM-1 levels compared with patients with no evidence of vascular disease (19.2+/-12.9 vs 7.9+/-11.8 mg/l, P<0.001 and 608+/-189 vs 474+/-155 ng/ml, P<0.005 respectively). CONCLUSIONS: Serum levels of ICAM-1, VCAM-1, and MCP-1 are increased in HD patients and probably result from either inadequate clearance or enhanced synthesis and release. HD session resulted in a significant increase of the above molecule levels but the exact mechanism(s) responsible for these alterations are yet to be fully elucidated. Increased levels of adhesion molecules are associated with inflammation, dyslipidaemia, and cardiovascular events. However, the potential link between these processes and its clinical significance warrants further investigation.